HIV, the virus that causes AIDS, can be diagnosed from a mouth swab as accurately as from a blood sample, Canadian scientists said.

Researchers from McGill University in Montreal said that their saliva HIV test OraQuick HIV 1/2 was 99 percent accurate for HIV in high-risk populations and about 97 percent in low-risk populations.

The oral test works by detecting whether HIV antibodies are present in a person's oral fluid and gives a result within 20 minutes.

"Testing is the cornerstone of prevention, treatment and care strategies," study leader Dr. Nitika Pant Pai said. "Although previous studies have shown that the oral fluid-based OraQuick HIV 1/2 test has great promise, ours is the first to evaluate its potential at a global level."

The research, which was published in the journal The Lancet Infectious Diseases, has major implications for countries that want to adopt self-testing strategies for HIV.

"Getting people to show up for HIV testing at public clinics has been difficult because of visibility, stigma, lack of privacy and discrimination," Pai added. "A confidential testing option such as self-testing could bring an end to the stigmatization associated with HIV testing."